Drying out of Switchgear

In this article, drying of switchgear is given by the Megger. The switchgear equipment is dried out before used in the system.

Insulation Resistance

• A 1000 V megger is used for measurement of insulation resistance, for higher rating motorized megger of 2.5 kV shall be used.
• The switchgear equipment first dried out before it is switched when

Insulation Resistance of switchgear

Insulation Resistance	Voltage Rating
< 1 Mega ohm	Rated 1000 V

Minimum Electrical Clearance For Outdoor Switchgear

 

Phase to Phase & Phase to Earth Clearance for Outdoor Switchgear

• The minimum clearance between phase to phase and phase to earth and sectional clearance for outdoor switchgear is given as below. 
• This clearance is specified by considering impulse voltage withstand level. 
• If the clearance is based on the transient overvoltage on the system, clearance may be higher in those cases.

Low Voltage, Medium Voltage & High Voltage

There are some importance Electrical definitions are given as per IE RULE 1956. All these definitions are given as per IE rules 1956.

Apparatus

• The apparatus means electrical apparatus including all machines its accessories in which conductors are used.